some emails bouncing back

[Kurgen]

Anyone got any ideas how to resolve this, its on my dads office 365 account, some valid emails are bouncing back

Undeliverable: FW: Building Regs Quote BR/2024/03589



Delivery has failed to these recipients or groups:

[email protected]
Your message couldn't be delivered. Despite repeated attempts to contact the recipient's email system it didn't respond.

Contact the recipient by some other means (by phone, for example) and ask them to tell their email admin that it appears that their email system isn't accepting connection requests from your email system. Give them the error details shown below. It's likely that the recipient's email admin is the only one who can fix this problem.

For more information and tips to fix this issue see this article: https://go.microsoft.com/fwlink/?LinkId=389361.

 

[Caged]

Send an email from your dad's account to [email protected] and post the results of the reply here

 

[Kurgen]

Send an email from your dad's account to [email protected] and post the results of the reply here

cheers will do

 

[Kurgen]

Send an email from your dad's account to [email protected] and post the results of the reply here

report below, i ve replaced the nameon email with test, so its not disclosed, but doesnt really matter





Thank you for using the verifier,

The Port25 Solutions, Inc. team

==========================================================
Summary of Results
==========================================================
SPF check: softfail
"iprev" check: pass
DKIM check: pass



--_005_LO2P123MB244731757AABE845824BED2FD6432LO2P123MB2447GBRP_--

 

[Kurgen]

Send an email from your dad's account to [email protected] and post the results of the reply here

ive also noticed sky uses yahoo for its email, so i can guess its limited to emails hosted by yahoo

 

[Glanza]

He might need DMARC setting up now as from today some third party email solutions won't accept email without valid SPF, DKIM & DMARC being setup.

 

[Caged]

==========================================================
Summary of Results
==========================================================
SPF check: softfail
"iprev" check: pass
DKIM check: pass

==========================================================
Details:
==========================================================

HELO hostname: GBR01-LO4-obe.outbound.protection.outlook.com
Source IP: 40.107.122.139
mail-from: [email protected]

----------------------------------------------------------
SPF check details:
----------------------------------------------------------
Result: softfail
ID(s) verified: smtp.mailfrom=[email protected]

DNS record(s):
hungerforddesign.co.uk. 300 IN TXT "MS=ms10904327"
hungerforddesign.co.uk. 300 IN TXT "v=spf1 +a +mx +ip4:89.187.86.9 +ip4:89.187.86.25 include:relay.mailchannels.net ~all"
hungerforddesign.co.uk. 300 IN A 109.169.83.162
hungerforddesign.co.uk. 300 IN MX 10 hungerforddesign-co-uk.mail.protection.outlook.com.
hungerforddesign-co-uk.mail.protection.outlook.com. 10 IN A 52.101.73.11
hungerforddesign-co-uk.mail.protection.outlook.com. 10 IN A 52.101.73.12
hungerforddesign-co-uk.mail.protection.outlook.com. 10 IN A 52.101.73.16
hungerforddesign-co-uk.mail.protection.outlook.com. 10 IN A 52.101.73.22
hungerforddesign-co-uk.mail.protection.outlook.com. 10 IN A 52.101.68.0
hungerforddesign-co-uk.mail.protection.outlook.com. 10 IN A 52.101.68.16
relay.mailchannels.net. 60 IN TXT "v=spf1 ip4:23.83.208.0/20 ip4:46.232.183.0/24 ip4:199.10.31.235/32 ip4:199.10.31.236/32 ip4:172.255.62.10/32 ip4:172.255.62.11/32 ip4:185.67.193.67/32 ip4:35.85.190.185/32 ~all"

Your DNS settings in Office 365 should have been screaming at you that this wasn't set correctly

Set up SPF identify valid email sources for your Microsoft 365 domain - Microsoft Defender for Office 365

Learn how to update a Domain Name Service (DNS) record to use Sender Policy Framework (SPF) with your custom domain in Office 365.

learn.microsoft.com

 

[Kurgen]

Your DNS settings in Office 365 should have been screaming at you that this wasn't set correctly

Set up SPF identify valid email sources for your Microsoft 365 domain - Microsoft Defender for Office 365

Learn how to update a Domain Name Service (DNS) record to use Sender Policy Framework (SPF) with your custom domain in Office 365.

learn.microsoft.com

thanks will take a look, but we didnt set anything up it was done by the office365 provider

 

[visibleman]

Anyone got any ideas how to resolve this, its on my dads office 365 account, some valid emails are bouncing back

Good tool to use for email delivery is https://mxtoolbox.com.
Otherwise MS365's DNS settings (Admin portal > Settings > Domains > Select your domain name > DNS Records tab) will highlight obvious DNS record issues.

But as others have mentioned, you need to make sure SPF and DMARC DNS records are correctly configured on your domain and ideally DKIM as well.

If that domain in the report is correct, then your SPF TXT record is missing Outlook from the third-party includes - MS365 SPF Info Here.
DMARC TXT record needs creating on your domain. The rua and ruf email address(es) needs to be valid; i typically set it to a distribution group and forward that users/members of the tenant that needs it - MS365 DMARC Info Here, MXToolBox Info Here.
Doesn't look like DKIM records are set either. You need to set your domain on your MS365 tenant as the primary/default (usually default to onmicrosoft domain) before your can add the prefix selector CNAME records - MS365 DKIM Info Here.

 

[Zefan]

Not sure on the sensitivity of the details, but you might want to trim out some of the address/phone details in the content of the email.

 

[Kurgen]

Not sure on the sensitivity of the details, but you might want to trim out some of the address/phone details in the content of the email.

its nothing thats not publicly available from the website, but i can remove the original post now its been answeered

 

[Kurgen]

so this is sorted now, i had to email the hosting company and the office365 company and between them they sorted it out